Apparatus and process for making a pressure electrical contact assembly for an electrical device

ABSTRACT

Protrusions formed in a case member of a compression bonded encapsulated electrical device act on a resilient member and accurately maintain the compression force acting on the electrical contacts and the semiconductor element of the device.

United States Patent [151 3,683,492 Meyerhoff et al. [451 Aug. 15, 1972 [54] APPARgTlJi AND PROCESS FOR [56] References Cited MAKIN RESSURE ELECTRICAL CONTACT ASSEMBLY FOR AN UNTTED STATES PATENTS ELECTRICAL DEVICE 2,604,923 7/1952 Shivoder ..29/5l1 X Ind 2,675,847 4/1954 Haegele; ..72/DlG. l [72] i z?gga ,g gzz gg 3,435,304 3/1969 Bezouska et al ..317/234 Primary Examiner.1ohn F. Campbell [7 3] Asstgnee: W Electric Corporation, Assistant Examiner-W. Tupman Pittsburgh, Pa. Attorney-F. Shapoe and C. L. Menzemer [22] Filed: Feb. 6, 1970 ABSTRACT [211 App}. 9'378 Protrusions formed in a case member of a compres- Related U.S. Application Data sion bonded encapsulated electrical device act on a resilient member and accurately maintain the com- [62] fir 2: Apnl 1968! pression force acting on the electrical contacts and the a one semiconductor element of the device. [52] U.S. Cl ..29/588, 29/203 R, 29/511, 29/569 [51] Int. Cl. ..B01j 17/00, H011 1/10 6 Clailm, 16 Drawing Figures [58] Field of Search 29/510, 511, 588, 203 D,

203 R, 29/569;72/D1G. 1; 317/234 PATENTEI] AUG 1 5 m2 SHEET 8 OF 6 PATENTEBMJB 15 1912 SHEET 3 BF 6 FlG.6.

PATENTEDAUGJ s 1972 SHEET 0F 6 FIG.I6.

FIG. IO.

PAIENTEDAus 15 1912 3.683.492 'SHEET 5 or 6 APPARATUS AND PROCESS FOR MAKING A PRESSURE ELECTRICAL CONTACT ASSEMBLY FOR AN ELECTRICAL DEVICE CROSS REFERENCE TO RELATED APPLICATION This patent application is a Division of copending US. Pat. application Ser. No. 720,062, filed on Apr. 10, 1968, now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a means for maintaining the compression force acting on a semiconductor element in a compression bonded encapsulated electrical device.

' 2. Description of the Prior Art Heretofore, two of the means for maintaining the compressive force on a semiconductor element and its associated electrical contacts embodied a retaining ring co-operau'ng with a thrust member acting on =at least one spring member or a hat shaped member externally threaded and threadedly engaging a case member within which the electrical contacts, the semiconductor element and the compressive force means were disposed. In either case X-ray analysis of assembled devices has shown that it is not possible to consistently duplicate the force loading on the semiconductor element of each device in a production run. One or more aperture spring washers, such, for example, as belleville, or disc shaped, spring washers, comprise the compressive force loading of each device, and the X- ray analysis clearly shows that the deflection of each washer and the spacing between adjacent washers, under load, is not the same between devices of the same design in the same production run and having the same force loading. Careful inspection and checking of torque requirements and loads exerted on the element confirm the inconsistencies. Improperly formed threades, burred threads, and dirt deposited in the threads are some of the reasons for the inconsistencies which were found.

SUMMARY OF THE INVENTION In accordance with the teachings of this invention there is provided apparatus and a process for making a pressure electrical contact assembly. A semiconductor element is placed within a tubular member upon a support closing of one end of the tube, the components being supported within suitable assembly apparatus. At least one electrical conductor is placed on the element and at least one resilient member is disposed on a portion of the conductor. The apparatus is then set into motion to apply a predetermined force upon the resilient member to force the conductor and the support member into a pressure electrical contact with the semiconductor element. When the predetermined force has been fully applied, a component of the apparatus is activated to deform the tubular member in at least two places, and preferably three places, immediately above the resilient member to retain the applied force on the resilient member, the conductor, the element and the support member.

DRAWINGS FIG. 1 is an elevation view, partly in cross-section, of a portion of an electrical device being processed in accordance with the teachings of this invention;

FIG. 2 is an elevation view, partly in cross-section, of a sub-assembly of the electrical device of FIG. 1;

FIG. 3 is an elevation view, partly in cross-section, of a portion of the apparatus embodied in the process of assembling an electrical device in accordance with the teachings of this invention;

FIG. 4 is a top view of a pressure electrical contact assembly being processed in accordance with the teachings of this invention showing the various possible staking, or dimpling, locations;

FIG. 5 is an elevation view, partly in cross-section, of one pressure electrical contact assembly made in accordance with the teachings of this invention;

FIG. 6 is an elevation view, partly in cross-section, of a portion of an electrical device embodying a preferred shape for the protrusions of the inner wall;

FIG. 7 is a top view of the device shown in FIG. 6;

. FIG. 8 is an elevation view, partly in cross-section, of a part suitable for use in the apparatus of FIG. 3;

FIG. 9 is a bottom view of the part shown in FIG. 8;

FIG. 10 is an elevation view, partly in cross-section, of an electrical device made in accordance with the teachings of this invention;

FIG. 11 is an elevation view, partly in cross-section of an alternate embodiment of the apparatus of FIG. 3,

FIG. 12 is an enlarged view of a portion of the apparatus of FIG. 1 1;

FIG. 13 is an elevation view, partly in cross-section, of an alternate embodiment of an electrical device made in accordance with the teachings of this invention;

FIG. 14 is a top view of a portion of the device of FIG. 13;

FIG. 15 is an elevation view, in cross-section, of a portion of the device of FIG. 13; and

FIG. 16 is an alternate embodiment of the electrical device of FIG. 10.

DESCRIPTION OF THE INVENTION This invention is suitable for making electrical devices, such, for example, as diodes, transistors and thyristors, embodying a semiconductor element having two or more regions of different type serniconductivity and to which two or more electrical connections are made by pressure means only. However, to more clearly describe the invention, and for no other purpose the invention will be described for the making of a thyristor embodying a semiconductor element having four regions of serniconductivity.

\Vith reference to FIG. 1 there is shown a sub-assembly 10 of an electrical device made in accordance with the teachings of this invention. The sub-assembly 10 comprises a support member 12 comprising a peripheral flange 14 and an upwardly extending pedestal portion 16. The upwardly-extending pedestal portion 16 has an uppermost mounting surface 18. The peripheral flange 14 has a top surface 20 and the upwardly-extending pedestal portion 16 has a peripheral side surface 22.

Thesupport member 12 is made of a metal selected from the group consisting of copper, silver, aluminum, base alloys thereof, and ferrous base alloys. Copper and brass, a base alloy of copper, have been found particularly satisfactory for this purpose.

An upwardly-extending hollow, or tubular, member 24 is affixed to the support member 12. The inner periphery of the member 24 conforms to the peripheral surface 22 of the pedestal portion 16. The member 24 is affixed to the support member 12 by any suitable means known to those skilled in the art, such, for example, as by disposing a suitable braze material between the top surface 20 of the flange 14 and the side surface 22 of the pedestal portion 16 and a portion of the inner periphery and part of the bottom surface of the member 24.

The member 24 is preferably made of a ferrous base material although other suitable materials, particularly metals, may be employed.

An electrical contact and thermal dissipating stud 26 is either affixed to, or is integral with, the support member 12. The stud 26 is used to connect the support member 12 to an electrical conductor and/or heat sink member.

A non-reactive, malleable, electrically and thermally conductive layer 28 is disposed on the uppermost mounting surface 18 of the support member 12. The layer 28 comprises a metal selected from the group consisting of gold, silver, tin, indium, lead and aluminum. The layer 28 compensates for, and conforms to, any surface irregularities which may occur on the surface 18. The layer 28 may be disposed upon the surface 18 by any suitable means known to those skilled in the art, such, for example, as electrodeposition means, or as a preformed disk of a suitable metal disposed on the surface 18, or afiixed to the surface 18 and then machined to specific requirements.

A semiconductor assembly 30, as shown in FIG. 2, is disposed on the malleable layer 28. The fusion assembly 30 comprises a four region semiconductor element 32 affixed to a first electrical contact 34 by a layer 36 of a suitable type solder or brazing compositron.

The electrical contact 34 comprises a metal, such, for example as molybdenum, tungsten, tantalum, and combinations and base alloys thereof. The contact 34 is a firm supporting structure for the semiconductor element 32. The contact 34 has relatively good electrical and thermal conductivity properties, as well as thermal expansion characteristics which are very similar to those of the semiconductor element 32.

The layer 36 of solder may comprise any suitable hard or soft solder known to those skilled in the art. Preferably, the solder layer 36 comprises solders, such, for example, as alloys of gold like gold-antimony which form eutectic compositions with silicon and also a metallurgical bond to molybdenum, tungsten, tantalum, and combinations and base alloys thereof as well as other gold alloy compositions, alloys of aluminum, and alloys of silver, each of which having a melting point above 350 and having a greater strength and hardness than the more common alloys of lead and tin.

It will be understood, of course, that the particular type of solder will depend on the anticipated operating temperature range of the finished electrical device.

A second electrical contact 38, most often called a gate contact, is electrically connected to the element 32, as well as a third electrical contact 40, in this instance being disposed about, and separate from, the gate contact 38.

Although not shown in FIG. 1, the semiconductor element assembly 30 may be axially aligned within the member 24 by any suitable means known to those skilled in the art, such, for example as by centering the assembly 30 within a cylindrical moisture gettering element or within a cylindrical locating member.

Referring again to FIG. 1, an apertured malleable layer 44 of an electrically and thermally conductive metal, such, for example, as one of those comprising the malleable layer 28, is disposed on the contact 40 of the fusion assembly 30. The purpose of the layer 44 is the same as layer 28. A multiple electrical contact assembly 46 is disposed partly on the second malleable layer 44. The contact assembly 46 comprises any such suitable materials and components necessary for a pressure electrical contact assembly such, for example, as a molybdenum washer 48 brazed to a partially hollow electrical connector 50 extending upwardly from the washer 48. An electrically insulating bushing 52 is slidably mounted inside the hollow portion of the connector 50.

A first electrical lead 56, suitably protected by a layer of electrically insulating material when required, extends through a slot 58 in the sidewall of the partially hollow connector 50 and down through the center of the hollowed-out portion terminating in a button shaped contact member 60. A force can be applied and maintained on the button-shaped contact member 60 by means of resilient force means 62 positioned within the connector 50 and acting on the peripheral shoulder of the bushing 52, the bushing 52 in turn acting on the contact 60. The contact member extends through the aperture of the layer 44 and is disposed on the contact 38 of the fusion assembly 30.

An electrical insulating washer 64 is placed over the partially hollow connector 50 of the contact assembly 46 and disposed on the washer 48. A first metal thrust washer-like member 66 is disposed on top of the insulating washer 64. At least one resilient member such, for example, as a convex spring washer 68 is placed over the hollow connector 50 and disposed on the thrust washer 66. A second metal thrust washer-like member 70 is placed over the hollow connector 50 and disposed on the spring washer 68.

With reference to FIG. 3, the assembled components are placed in a press 80. The assembled components are nested in a movable support fixture 82 which seats the components and axially aligns them beneath a rigidly mounted structure 84 of the press 80. A plunger-stop 86 is slidably mounted in the rigidly mounted structure 84 of press and is free to move vertically up and down. The plunger-stop 86 is also axially aligned with the vertical axis of the assembled components by internally engaging a portion of the hollow member 24. The plunger-stop 86 has a recessed portion 88 which permits portions of the contact assembly 46 to be nested within the plunger-stop 86 while having the remainder of the lower end surface 90 resting on the second metal thrust member 70.

The press operation raises the movable support fixture 02 of the press 80 forcing the washer 70 against the end face 90 of the plunger-stop 86. No appreciable force is applied to the assembledcomponents until the face 90 is resting securely on washer '70 and the upper end surface 92 of the peripheral flange of the plungerstop 86 is flush against a striking plate 94 of the rigidly mounted structure 84. The end face 90 of the plungerstop 86 and the point 96 of each staking, or dimpling, tool 98 are now in essentially the same plane.

The continued upward movement of the movable support fixture 82 and sub-assembly l0, continually depresses the spring washer 68 further while still maintaining the planar relationship of the end face 90 and the point 96 of the staking tool 98. The upward movement is continued until a predetermined force, suffrcient to assure a good pressure electrical contact assembly for a given assembly, is reached and then means 100 is actuated, usually pneumatically, moving the staking tools 93 horizontally towards the vertical axis of the assembled components now under load. The staking tool 98 movement continues until a portion of the member 24 above the washer 70 is deformed by pushing a portion of it horizontally inwardly to protrude above the washer surface 70 of FIG. 1. The protrusion so formed is denoted as 102.

Preferably the press 80 has three staking tools so that three protrusions, denoted as 102, can be made simultaneously. The tools are then retracted horizontally.

Pressure is then released from the movable support fixture 82 and the protrusions 102 retain the assembled components in compression. It is to be noted that since the point 96 and the end surface 90 lie in the same plane, little, if any, relaxation of the convex spring washer 68 can occur. Moreover since the springs are compressed to a precisely predetermined load and the upper surface of the metal thrust washer 70 is essentially in the same plane as tool point 96 the spring force is maintained after the staking operation regardless of dimensional tolerances. Therefore, it is readily seen that for any given type of assembly, consistently uniform quality of pressure electrical contact devices is obtained.

Referring now to FIG. 4 there is shown the assembled components after staking and removal from the press 80. Although two protrusions, or dimples 102, spaced 180 apart, will hold the components in compression, preferably three protrusions, or dimples, 102 are formed to act against the second metal thrust washer 70 thereby maintaining the pressure electrical contact assembly. Each dimple 102 is preferably 120 apart from the adjacent dimples 102. In instances where the devices are of sufficiently large area and a high force is exerted on the components, additional dimples 102 may be formed as required. Since a three staking tool press is employed in this process, the assembled components can, before withdrawal from the press, be rotated 60, the same force applied, and three additional dimples 102 formed. It is to be noted that since the face 90 and the bottom surface of the point 96 of each tool 98 lie in the same plane, and since the force of the press is the same in each operation, the bottom surface of all the dimples 102 will essentially be in the same plane and the top surface of the washer 70 should also be essentially in the same plane as the face 90 and the bottom surface of the point 96 of each tool 98. The formation of two dimples 102, 180 apart from each other has often been found insufficient to produce device quality assemblies of a consistently good quality standard level. In instances where only two dimples 102 are employed, deformation of the thrust member may occur between the two dimples 1102, resulting in a partial relaxation of the compressed components. Therefore, at least three dimples, 120 apart is preferred.

Referring again to FIG. 3 the plunger-stop 86 of the press preferably has one or more keyways to provide vertical movement of the plunger-stop 86 without rotation. Additionally the continuance of the keyway all the way through the end surface 90 provides a clearance hole for the point 96 of the staking tool 90.

With reference to FIG. 5 there is shown the assembled components, after the formation of three dimples 102. The dimples 102 acting against the second metal thrust washer 70 act on the convex spring washer 68 to resiliently urge the multiple contact assembly 46, the semiconductor element 30, and the support member 12 into an electrical and thermal conductive relationship. The applied force forces the washer 48 into a pressure electrical contact with the contact 40 of the semiconductor element '30. Meanwhile the applied force also results in a pressure electrical contact between the button contact 60 and the gate contact 38 of the semiconductor element by means of the coil spring 62 acting on the slidable insulator 52.

Preferably, the dimples 102 have a shape corresponding to one quarter of a hemisphere. The preferred shape of the dimple and its relationship to the surface of the spring washer is shown in FIGS. 6 and 7. The preferred shape of the dimple gives maximum resistance to the shearing force imparted by the compressed spring washer which is trying to shear the dimple away from the member 24.

Since the preferred shape of the dimple 102 is similar to one quarter of a hemisphere, the shape of the point 96 of the staking tool 98 (FIG. 3), is accordingly shaped like one quarter of a sphere.

If, upon physical or electrical examination, the assembled components of FIG. 5 are found unsatisfactory, a reworking is possible. The press 80 (FIG. 3) is operated in the same manner as before except that the plunger-stop 86 is replaced by a reworking tool 300 (FIG. 8) for pushing the dimples 102 back into the wall of the member 24. Referring now to FIGS. 8 and 9, the reworking tool 300 comprises a shaft 302 axially aligned, and partly disposed within a hollow member 304. The shaft 302 has a peripheral shoulder 306 near the top end and a peripheral shoulder 308 about its lower end. A spring 310 is disposed about the shaft 302 between the top end 312 of the member 304 and the shoulder 308 of the shaft 302.

Slots 314 are disposed in the lower external peripheral surface portion of the member 304. Disposed within each of these slots 314 is a finger 316 pivotally engaged at its upper end 310. The number of slots 314 is dependent on the number of dimples 102 which one wishes to rework at the same time. Preferably three slots 314 are employed since devices having three and six dimples 102 are most commonly manufactured at this time.

The lower portion of the member 304 is recessed to fit within the hollow member 24 of a sub-assembly 10 with the end 320 resting on the second thrust washer 70. The tool 300 is so designed that in its unloaded position the spring 310 forces the shaft 302 up far enough that the shoulder 308 engages a notch 322 in each of the fingers 316 causing the lower end of each finger 316 to be withdrawn within the lower end of the slot 314. This provides clearance for indexing the tool 300 by the dimples 102 of the sub-assembly 10 being reworked.

The tool 300 is substituted for the plunger-stop 86 in the press 80. As the movable support fixture 82 moves upward, the shoulder 308 engages the striking plate 94. Further upward movement of the fixture 82 causes the member 304 to continue its upward movement thereby compressing the spring 310. Relatively speaking the shaft 302 is moving downward through the hollow member 304, the outer peripheral surface of its shoulder 308 pushing and sliding against the fingers 316. The further the member 304 moves upward, the further down on each finger 316 the shoulder 308 works thereby forcing the fingers 316 outward at its bottom end and against the dimples 102 engaged in each slot 314. When the bottom surface of the shoulder 308 is flush with the end surface 320 of the member 304, the outer surface of each finger 316 is flush with the outer peripheral surface of the lower portion of the member 304 and the dimples 102 have been reworked to permit the removal of the washer 70 and the other components of the sub-assembly 10. Additionally at this time the force of the press 80 acting on the tool 300 and the washer 70 is exactly the same force that was required to assemble the components initially.

The load, or force, is relieved in the press 80 and the tool 300 is indexed to rework other dimples 102 or to remove the sub-assembly 10 from the movable fixture 82 for disassembling of the components for reworking.

After reworking, the components are then reassembled in the same manner as before and as shown in FIG. 1, placed in the press 80 as shown in FIG. 3, and indexed to expose virgin wall material to the point 96 of the tool 98. Restaking is then performed in the same manner as before, the force exerted on the assembled components by the press 80 being the same as before.

It has been found that if only three dimples 102 are employed to form the pressure electrical contact, the member 24 can be reworked at least twice before being discarded. If six dimples 102 are employed to form the pressure electrical contact, the member 24 is reworked only once before being discarded. If six dimples 102 are employed to form the pressure electrical contact, the member 24 is reworked only once before being discarded.

It is to be noted that only the same force applied in forming a pressure electrical contact is required to rework the dimples for disassembly of the components and for reassembling reworked components.

When a satisfactory pressure electrical contact assembly is made, the electrical device is completed as shown in FIG. 10. The pressure electrical contact assembly is hermetically sealed within a header assembly 104 affixed to a weldring 106 formed on the member 24. The connector 50 is electrically connected to an electrical connector 108 hermetically sealed in the assembly 104. The lead 56 is electrically connected to the hollow connector 110 hermetically sealed within the assembly 104 thereby completing the hermetic sealing of the pressure electrical contact assembly.

Electrical devices made in accordance with the teachings of this invention are more easily and accurately assembled and can be more easily reworked if a malfunction should occur. Additionally X-ray examination shows that the compression of the assembled components of the pressure electrical contact is essentially the same for all devices of the same type for the same applied force as compared to prior art devices which when analyzed show a wide variation in degrees of compression. Additionally a product of a consistently good quality level is obtainable at all times.

Another modification of this invention is shown in FIG. 11. In this instance the staking tool 98 with the point 96 of the press 80 is replaced with a roll forming tool 101 which rotates about an axis 99 and a shaft 97. The movable support fixture rotates about the symmetrical axis 89 which is coincidental with that of the semiconductor device. In this instance the plunger-stop 86 is completely round and all keyways have been eliminated. The upper end surface 92 is seated against an anti-friction thrust bearing 87 which is located in a recess in striking plate 94. An enlarged view of the relationship of the various components is shown in FIG. 12. The embodiment results in one continuous reduced section which acts on the entire outer peripheral top surface of the thrust member to form the desired premure electrical contact assembly. However, salvage of the piece parts in case of a faulty subassembly is more difficult than the prior preferred embodiment.

With reference now to FIG. 13, there is shown an alternate embodiment of a compression bonded electrical device 200 embodying a dimpling means 202 to obtain a pressure electrical contact between a body of semiconductor material and two or more electrical contacts electrically connected to the body.

In order to more aptly describe the alternate embodiment, and for no other purpose, the device 200 will be described as embodying three electrical connections electrically connected by pressure means only to a body of semiconductor material.

The electrical device 200 comprises a support member 204 having two upright spaced apart members 206 and 208. The material comprising the members 204, 206 and 208 are electrically and thermally conductive and is one selected from the group consisting of copper, copper alloys, aluminum, aluminum alloys and ferrous base alloys.

Disposed on the member 204 between the members 206 and 208 is a semiconductor assembly 210. With reference to FIG. 14 there is shown the semiconductor assembly 210 comprising a body 212 of semiconductor material and electrical contacts 214, 216 and 218. Each of the electrical contacts 214, 216 and 218 are made of an electrically conductive material.

The body 212 of semiconductor material is suitably prepared to function as a controlled rectifier and comprises such, for example, as a first emitter region, a fust base region, a second base region, and a second emitter region. A layer 220 of electrically conductive material is disposed on the first emitter region. A layer 222 of electrically conductive material is disposed on the first base region.

Referring now to FIG. 15, there is shown a plan view of the electrically conductive layers 220 and 222 The two regions 220 and 222 are electrically isolated from ffilch other by a continuous gap 224 disposed between With reference again to FIG. 14, the contact 218 is preferably permanently affixed to the second emitter region of the body 210 of semiconductor material. The contact 218 serves as a fusion support for the body 210 and comprises a suitable electrically conductive material such, for example, as molybdenum, tungsten, tantalum, combinations and base alloys thereof. The contact 218 is disposed on the electrically and thermally conductive support member 204. The electrical contact 214 is electrically connected to the first base region of the body 210 by the layer 222. The electrical connector 216 is electrically connected to the first emitter region of the body 210 by the layer 220.

An electrically non-conducting material 226 secures in place within a hermetic enclosure and electrically insulates at least part of the electrical conductors 214 and 216.

With reference to FIG. 13 again, the ends of a resilient spring member 228, which has a bowed configuration, are held in place by the dimpling means 202. The dirnpling means 202 are formed after the spring member 228 has been placed convex side down on the insulator 226. The ends of the member 228 are forced downward a predetermined distance or until a predetermined force level is reached on a ram applied to the members end. While depressed, the upright members 206 and 208 are deformed inwardly, or crimped or dimpled, to engage the ends of the spring member 226. The crimped portion of the members 206 and 208 exert a force on the member 228 which in turn through the convex portion exerts a force on the insulator 226 thereby forming pressure electrical contacts of conductors 214 and 216 onto the electrical contacts 222 and 220 respectively which are an integral part of the element 210 affixed to the contact 218 and between contact 218 and the support member 204. A layer 230 of an electrically insulating material forms a hermetic enclosure for the element 210.

With reference to FIG. 16 there is shown an alternate embodiment of this invention. The device as shown is exactly the same as the device in FIG. except that it has been found that the second thrust member70 may be eliminated and the dimples I02 acting directly on only one spring member 68 consistently produce reliable compression bond encapsulated electrical devices.

We claim as our invention:

1. Apparatus for making a pressure electrical contact assembly comprising a. a support member movable along an axis thereof,

b. means on said support member for supporting a relatively thin-walled tubular member with the axis thereof being aligned with the axis of the support member, the tubular member having disposed therein a flat surfaced semiconductor element, a resilient member means disposed to be compressed so as to apply a pressure to the flat surface of the semiconductor member and at least one electrical conductor having a flat surface capable of being in pressure contact with a flat surface of the semiconductor member, when the resilient member means is compressed,

c. means having a portion projectinginto the tubular member with a face contacting the upper surface of the resilient member means for applying a predetermined force to the resilient member as the support member is moved along its axis, means to compress the resilient member means and thereby to press the semiconductor member against the electrical conductor; and

at least two staking members associated with both the support member and the means for applying a predetermined force, each staking member having a pointed projection with a bottom surface essentially in the same plane as the face of the said por tion projecting into the tubular member, means for forcing the pointed projections of the staking member into the walls of the tubular member when the predetermined force has been applied to the resilient members, whereby at least two narrow inward protrusions are produced in the walls of the tubular member by the staking members, each of the narrow inward protrusions having a lower surface engaging the upper surface of the resilient member means to fix and hold the resilient member means in the precise position where it exerts the predetermined force on the surface of the semiconductor member.

2. The apparatus of claim I, wherein the means having a portion projecting into the tubular member for applying a predetemiined force to the resilient member means comprises a hollow tubular member with a flat end face, and at least three slots therein at said end face to accommodate the pointed projections of at least three staking members, as said pointed projections force in the walls of the tubular member.

3. The apparatus of claim 2 wherein each staking member has means to move the pointed projection thereof at right angles to the axis of the tubular member.

4. The apparatus of claim 1 in which said pointed projection is shaped to conform to one quarter of a sphere and the bottom surface is of a flat semicircular shape.

5. The apparatus for disassembling compression bonded semiconductor devices comprising a tubular member containing a semiconductor device with a resilient member applying a force thereto and a plurality of protrusions in the wall of the tubular member holding the resilient member under pressure, which comprises a relatively stationary component comprising a hollow member and a slidable shaft member having a portion movable within said hollow member axially aligned with each other;

said hollow member having opposed end faces, one of said end faces comprising in part an end face portion fitting within the tubular member for contact with said resilient member;

a plurality of spaced elongated slots corresponding to the number and spacing of the protrusions in the tubular member, formed in the interior walls of said hollow member, each of said slots extending from said end face in contact with said resilient member to a closed end at a point short of the other end face;

a finger-like tool member disposed in each of said slots, each of said tool members having one end pivotally mounted in the upper closed end of each of said slots, and the other end movable about said pivotal mounting perpendicular to the said axis, said other end comprising a tool point for pushing said protrusions back for forming the walls of said tubular member into a relatively smooth inner surface;

resilient means disposed on said slidable shaft member to enable relative vertical movement of said hollow member and the shaft member; and

the portion of said slidable shaft member movable within the hollow member being adapted to move within the hollow member as the end face of the hollow member is arrested by contact with the resilient member in the semiconductor device, and said portion of the slidable shaft member moves into the hollow member and imparts movement to said finger-like tool member to push back the protrusions.

6. The apparatus of claim 5 in which said portion of said slidable shaft member to impart movement to said finger-like tool member comprises an outwardly extending flanged portion, the outer peripheral surface of which acts against each fmger-like tool member as said slidable shaft member and said hollow member move relative to each other, the relative downward movement of said slidable shaft member causing said peripheral side surfaces of said outwardly extending flange portion to push said other end of each finger-like tool member away from the vertical axis of said relatively stationary component and to reform a portion of said tubular member and the relative upward movement of said slidable shaft member causing the tool point of each finger-like tool member to move inwardly toward the vertical axis of said relatively stationary component. 

1. Apparatus for making a pressure electrical contact assembly comprising a. a support member movable along an axis thereof, b. means on said support member for supporting a relatively thin-walled tubular member with the axis thereof being aligned with the axis of the support member, the tubular member having disposed therein a flat surfaced semiconductor element, a resilient member means disposed to be compressed so as to apply a pressure to the flat surface of the semiconductor member and at least one electrical conductor having a flat surface capable of being in pressure contact with a flat surface of the semiconductor member, when the resilient member means is compressed, c. means having a portion projecting into the tubular member with a face contacting the upper surface of the resilient member means for applying a predetermined force to the resilient member as the support member is moved along its axis, means to compress the resilient member means and thereby to press the semiconductor member against the electrical conductor; and d. at least two staking members associated with both the support member and the means for applying a predetermined force, each staking member having a pointed projection with a bottom surface essentially in the same plane as the face of the said portion projecting into the tubular member, means for forcing the pointed projections of the staking member into the walls of the tubular member when the predetermined force has been applied to the resilient members, whereby at least two narrow inward protrusions are produced in the walls of the tubular member by the staking members, each of the narrow inward protrusions having a lower surface engaging the upper surface of the resilient member means to fix and hold the resilient member means in the precise position where it exerts the predetermined force on the surface of the semiconductor member.
 2. The apparatus of claim 1, wherein the means having a portion projecting into the tubular member for applying a predetermined force to the resilient member means comprises a hollow tubular member with a flat end face, and at least three slots therein at said end face to accommodate the pointed projections of at least three staking members, as said pointed projections force in the walls of the tubular member.
 3. The apparatus of claim 2 wherein each staking member has means to move the pointed projection thereof at right angles to the axis of the tubular member.
 4. The apparatus of claim 1 in which said pointed projectIon is shaped to conform to one quarter of a sphere and the bottom surface is of a flat semicircular shape.
 5. The apparatus for disassembling compression bonded semiconductor devices comprising a tubular member containing a semiconductor device with a resilient member applying a force thereto and a plurality of protrusions in the wall of the tubular member holding the resilient member under pressure, which comprises a relatively stationary component comprising a hollow member and a slidable shaft member having a portion movable within said hollow member axially aligned with each other; said hollow member having opposed end faces, one of said end faces comprising in part an end face portion fitting within the tubular member for contact with said resilient member; a plurality of spaced elongated slots corresponding to the number and spacing of the protrusions in the tubular member, formed in the interior walls of said hollow member, each of said slots extending from said end face in contact with said resilient member to a closed end at a point short of the other end face; a finger-like tool member disposed in each of said slots, each of said tool members having one end pivotally mounted in the upper closed end of each of said slots, and the other end movable about said pivotal mounting perpendicular to the said axis, said other end comprising a tool point for pushing said protrusions back for forming the walls of said tubular member into a relatively smooth inner surface; resilient means disposed on said slidable shaft member to enable relative vertical movement of said hollow member and the shaft member; and the portion of said slidable shaft member movable within the hollow member being adapted to move within the hollow member as the end face of the hollow member is arrested by contact with the resilient member in the semiconductor device, and said portion of the slidable shaft member moves into the hollow member and imparts movement to said finger-like tool member to push back the protrusions.
 6. The apparatus of claim 5 in which said portion of said slidable shaft member to impart movement to said finger-like tool member comprises an outwardly extending flanged portion, the outer peripheral surface of which acts against each finger-like tool member as said slidable shaft member and said hollow member move relative to each other, the relative downward movement of said slidable shaft member causing said peripheral side surfaces of said outwardly extending flange portion to push said other end of each finger-like tool member away from the vertical axis of said relatively stationary component and to reform a portion of said tubular member and the relative upward movement of said slidable shaft member causing the tool point of each finger-like tool member to move inwardly toward the vertical axis of said relatively stationary component. 